You are here:

Ophthalmology & Optometry/Physiological Reaction to Flashlight in Eyes


Can you explain the physiological process that occurs when a sudden bright light is shined in my eyes?  I can tell you that instantly everything goes bright white, and if the flashlight is a super powered LED one, it is a searing almost burning white.  There's an instant headache with nausea.  The super bright light causes vertigo.  I am clumsy to walk away.   Recovery is typically 10-15 minutes but in the severe cases it's gone 30 minutes and longer.  And what I mean by "recovery" is time from bright white when vision returns.  During that time there is a "film" over everything that grows progressively smaller, close to a circle in shape but somewhat oblong.  That shape has a jagged halo that is more yellow/red.    I'm recalling this from memory.  Unfortunately I expect I will experience the problem again in the near future and will give conscious attention to what I am actually "seeing" as sight returns.   I am usually more involved with it "hurting" my eyes and making me overall "not feeling well".

One of the security people where I live does not like me and finds it amusing to shine the flashlight in my eyes.  He did it three times tonight less than 3' away from me.  Fortunately it was a small flashlight and not too powerful.   Otherwise, I might still be blind.  I feel just as assaulted as if he walked up and slapped me across the face.

First, I would tell this story - forward this email - to your building supervisor, head of security, landlord, etc.  This abuse needs to be addressed.
When light enters the eye it triggers certain photochemicals in the back of the eye--these are pigments in the rods and cones.  That triggering leads to the sensation of sight, or vision.  It takes some time for these 'bleached' pigments to regenerate. While they're regenerating, there tends to be an after-image.
If the lights are causing headaches, etc, you may be having a visually-triggered migraine.
If the time to regenerate is more than a few seconds to a minute, you may want to see an eye doctor, a retinal specialist, specifically, to make sure that your recovery time isn't a sign of retinal problems.  Some people are born with long recovery times, but if it's progressive or changing it may be the sign of a condition that needs to be addressed.
My opinion is to make an appointment with your eye doctor for a comprehensive, dilated eye exam.  If they don't find anything, request a retinal consult.
Good Luck!

Ophthalmology & Optometry

All Answers

Answers by Expert:

Ask Experts


John M. Dovie, OD, FAAO


As a residency-trained Fellow of the American Academy of Optometry I am able to answer most questions regarding eye and vision health. Anything is welcome, ranging from dry or allergy eyes, bifocal contact lenses, or thoughts on LASIK surgery. As I am not a surgeon, detail-oriented surgical-related questions may be better answered by an ophthalmologist.


Selected to participate in the PCO residency program in Philadelphia at The Eye Institute, where I worked OD and MD specialists gaining invaluable experience in various clinics including glaucoma, cornea and cataract, oculo-plastics, retinal disease, neuro-ophthalmic disease, primary care, emergency medicine, and special populations. Have practiced and trained in numerous settings including hospital, academic, retail and private practice. I earned my Fellowship in the American Academy of Optometry (FAAO). There are currently only about 3000 active fellows worldwide, and there are only about 70 Fellows in the state of Virginia. I currently own and operate my own optometric practice/clinic.

American Academy of Optometry, American Optometric Association (Contact Lens/Cornea Section member since 2001), Southwest Virginia Optometric Association, Virginia Tech Alumni Association

“Nyctalopia as the Presenting Sign of Vitamin A Deficiency: A Late Complication of Gastric Bypass Surgery.” Clinical Case Study Poster presented at The American Academy of Optometry Denver, Colorado, December 2006, co-authored with Bradley Lane, OD.
“The Importance of Considering Paranasal Sinus Mucocele as a Differential Diagnosis in Diplopia.” Clinical Case Study Poster presented at The American Academy of Optometry San Diego, California, December 2005, co-authored with Kelly Malloy, OD, FAAO and Cherie Farkash, OD.
“Acute Onset of Halos and Glare: Bilateral Keratitis—An Atypical Presentation of Amiodarone Keratopathy.” Clinical Case Study Poster presented at The American Academy of Optometry Tampa, Florida December 2004. Also Presented to New Jersey Academy of Optometry, Neptune, New Jersey March 2005.
“The Opportunity for an Optometrist to Save a Life.” Clinical Case Study and Grand Rounds Presentation presented at The Pennsylvania College of Optometry, Philadelphia, Pennsylvania, September 2004.
“Corneal whorls cause wonder.” Clinical Challenges Quiz, co-authored with Andrew Gurwood, OD, FAAO, Review of Optometry. Published 10/15/2006.
“Acute onset of halos and glare: bilateral corneal epithelial edema with cystic eruptions--atypical presentation of amiodarone keratopathy.” Co-authored with Andrew Gurwood, OD, FAAO. Published February, 2006, Optometry.
“Pondering the posterior polka-dots.” Clinical Challenges Quiz, co-authored with Andrew Gurwood, OD, FAAO, Review of Optometry. Published 5/15/2005.
Professional Involvement:
“AION: Amiodarone-Induced or Anterior Ischemic Optic Neuropathy?” Participated as a peer-review referee for Expert Review of Ophthalmology (London, UK); refereed 10/2006.

Bachelor of Science, Cum Laude, Virginia Tech. Bachelor of Science, Pennsylvania College of Optometry. Doctorate (OD), Pennsylvania College of Optometry Residency, Pennsylvania College of Optometry Fellow of the American Academy of Optometry

Awards and Honors
Winner, First Place, "Best Beside Manner" by Our Health Magazine: 2012, 2013, 2014 Winner, First Place, "Best Eye Doctor" by The Roanoke Times: 2013, 2014 Recognized as a Fellow of the American Academy of Optometry, December, 2006 Recipient of the Onofrey G. Rybachok Memorial Scholarship, 2000-2001 Member: The Golden Key International Honor Society Member: The National Biological Honor Society Member: The National Honor Society Eagle Scout awarded 1994

©2017 All rights reserved.

[an error occurred while processing this directive]